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It is known that one of the reasons that causes the need for the process of balancing the spindles of grinding and highspeed milling machines is vibration, which is caused by the unbalance of the technological system. One of the most common
reactions to vibrations is a decrease in the speed of rotation of the spindle, which reduces the efficiency of high-speed machining. This fact is crucial for many machine tool manufacturers, who recommend balancing the tool, both before installation on
the machine spindle, and during machining. On the workpiece the main effect is expressed in decrease of surface quality and
precision of required dimensions, which reduces the service life of the spindle unit, tool, and, in the end all cutting machine.
Modern manufacturing operations require the use of high-speed machining at spindle speeds of more than 10,000 revolutions
per minute. Therefore, to reduce the level of vibrations and increase the service life of the metal-cutting machine, it is necessary to
provide for balancing the cutting tool and its mandrels. To achieve optimal results, balancing should be performed at each tool
change, which requires the availability of scientifically-based balancing techniques and appropriate technological equipment.
The work considered the latest publications on this topic, which are presented in the public domain, including the Internet.
High processing speed is used in many machining industries. One of the obvious benefits of this trend is to achieve greater
efficiency and productivity of the cutting process due to higher spindle speeds. However, increasing the speed of rotation of the
spindles leads to side effects in the machine and the workpiece due to increased vibration, as the centrifugal forces increase,
and the process system is destroyed. At the same time, the main factor that generates machine vibrations is the imbalance of
the technological system, since the spindles of high-speed grinding and milling machines are balanced in accordance with ISO
standards, the main source of imbalance is the tool and its mandrels.
The purpose of this scientific work is to conduct research on the balancing processes of high-speed grinding and milling
machines, taking into account the unbalance of the cutting tool, as well as the formation of information support for the design
process of a spindle assembly with corrective masses using Microsoft Access software.
Today, more and more manufacturers are using high-speed processing during technological operations, which makes balancing the tool and its mandrels a priority. The main effect of high-speed processing on grinding and high-speed milling machines is
to reduce machine time due to the intensification of cutting modes, as well as to increase the accuracy and quality of the cutting
process. The basis of high-performance high-speed processing can be the correct choice of parameters of cutting modes (machine,
NРC system, cutting tool, auxiliary tool with its fixing system, programming system, qualification of the machine operator and
other factors), and neglect of at least one of these factors can lead to a technological defect of the product.
The conducted studies have shown that various regulatory documents normalize the value of the residual imbalance, which
makes it possible to theoretically assess the value of unbalance of grinding wheels and milling cutters in the state of delivery,
and its change during operation. However, in the calculations for balancing grinding and high-speed milling machines, as a
rule, a number of assumptions are made, which makes it difficult to determine the residual imbalance and the accuracy class of balancing. Experimental studies of changes in the residual imbalance are few and specific. The paper also provides information support for the design process of a spindle assembly with corrective masses. On the basis of a number of diameters of
spindles and diameters of angular contact bearings, a database has been created for a number of standard sizes of correcting
masses using Microsoft Access software. |
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